MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
IMAGE CAPTION P50086
September 15, 1998
Jupiter's Inner Satellites
and Ring Components
This schematic cut-away view of the components of Jupiter's ring
system shows the geometry of the rings in relation to Jupiter and to
the small inner satellites, which are the source of the dust that
forms the rings.
The innermost and thickest ring, shown in gray shading, is the halo
that ends at the main ring. The thin, narrow main ring, shown with
red shading, is bounded by the 16-kilometer-wide (10-miles) satellite
Adrastea and shows a marked decrease in brightness near the orbit of
Jupiter's innermost moon, Metis. It is composed of fine particles
knocked off Adrastea and Metis. Although the orbits of Adrastea and
Metis are about 1,000 kilometers (about 600 miles) apart, that
separation is not depicted in this drawing. Impacts by small
meteoroids (fragments of asteroids and comets) into these small, low-
gravity satellites feed material into the rings. Thebe and Amalthea,
the next two satellites in increasing distance from Jupiter, supply
dust which forms the thicker, disk-like "gossamer" rings. The
gossamer rings, depicted with yellow and green shading, are thicker
because the source satellites orbit Jupiter on inclined paths
These small satellites all orbit closer to Jupiter than the four
largest "Galilean" satellites, Io, Europa, Ganymede and Callisto,
which were discovered nearly 400 years ago. The orbital distances of
the moons are drawn relative to the size of Jupiter.
The Jupiter image was created from a map based on data obtained by
the Hubble Space Telescope.
JPL manages the Galileo mission for NASA's Office of Space Science,
Washington, DC. The images are posted on the Internet at
http://photojournal.jpl.nasa.gov/ and at
http://www.jpl.nasa.gov/galileo . Background information and
educational context for the images can be found at:
http://www.jpl.nasa.gov/galileo/sepo .
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9/10/98 JP